Fund and stock, which is the better investment measure?

I used to buy and sell stocks, which helped me get less than 10,000 yuan, but now, I wonder whether I should buy stocks or fund.
Last year, my colleagues bought fund and gained more than 100,000yuan, which is far more than I have earned in the December of 2006.
So, I think that what I should do is to enhance the entrance of selling stocks, one yuan, this is the new principle for me to sell the stocks, and at least holding cannot be less than one month, unless the gain has agreed to my gaining threshold.